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View Full Version : is this normal for d2



franklin
07-24-2011, 07:13 AM
yhis is my first heat treat of d2 in my new oven, ok this is what i did foil wrap into cold oven, then to 1400 for 10 min then ramped to 1880 for 30 min, then plate quenched, then since i did not think it would hurt or even help ithruogh in freezer for two hours. well my point is there were two knives 1 1/8 thick turned grey all over just like when i would send them in to get done the 2nd one is colored differently is this ok heres a pic,now im going to temper on low side at 425 for 2 hours 2 x then peter martin said he would rc for me. what you think? will the 2nd one be ok?

Justin King
07-24-2011, 07:57 AM
Some colors and oxides are not unusual, but can indicate air infiltration in the foil, too much air inside the foil when it was sealed, or possibly a contaminant on the steel when it was wrapped. It is possible to get decarb on foil wrapped blades. Trouble is a hardness test dosen't tell you anything about the hardness right at the cutting edge because the test cant be done at that location, and the decarb can be just a spot here or there. When in doubt I put an edge on it and start carving hard on pieces of scrap steel, then inspect the edge. Decarbed areas will roll pretty heavily under this use.

franklin
07-24-2011, 11:29 AM
well ill be testing that one pretty heavy to see how she holds up,to bad i did not heat that one before i ground it like the smaller one but thought 3/16 would be ruf going after heat treat. still going to have them rc'd to see were heat treat put them thanks justin

Knifemaker.ca
07-24-2011, 03:34 PM
Did you leave the foil on for the plate quench?

franklin
07-24-2011, 04:32 PM
yes left it on till it was warm to touch then sniped the ends right to freezer, have you guys seen it like this before?

Knifemaker.ca
07-24-2011, 07:37 PM
Kind of looks like the envelopes may have been compromised. D2 usually comes out pretty shiny.